Cyclopropanation and Carbonyl Olefination Utilizing 2-(Alk-1-yn-1-yl)-2-(trialkylsilyl)-1,3-dithianes via Regioselective Generation of Titanium Alkynylcarbene Complexes
作者:Takeshi Takeda、Makoto Ozaki、Shuichi Kuroi、Akira Tsubouchi
DOI:10.1021/jo050122f
日期:2005.5.1
Cp2Ti[P(OEt)3]2-promoted reactions of 2-(alk-1-yn-1-yl)-2-(trialkylsilyl)-1,3-dithianes (RS)2C(Si)C⋮CR with terminal olefins and carbonyl compounds produced (trialkylsilylethynyl)cyclopropanes and 1-(trialkylsilyl)alk-3-en-1-ynes, respectively. These compounds were suggest to be produced via the formation of intermediary titanium α-(trialkylsilylethynyl)carbene complexes Cp2TiC(R)C⋮CSi in preference to their
Cp 2 Ti [P(OEt)3 ] 2促进了2-(alk-1-yn-1-yl)-2-(trialksilsilyl )-1,3-dithianes(RS)2 C(Si)C⋮的反应具有末端烯烃和羰基化合物的CR分别产生(三烷基甲硅烷基乙炔基)环丙烷和1-(三烷基甲硅烷基)alk-3-en-1-ynes。这些化合物被认为是通过形成中间体钛α-(三烷基甲硅烷基乙炔基)碳烯络合物Cp 2 Ti C(R)C⋮C Si而不是其区域异构体,α-(三烷基甲硅烷基)炔基碳烯络合物Cp 2 Ti C(Si C⋮CR。